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[Bill Irwin]

On a standard 386 PC AT running SCO XENIX System V/386 2.3.2, one can use
the  Chantal  (San Diego) Subsystem Software which takes over  low  level
system  management  of  SCSI  devices,  controllers,  file  systems  etc.
through a linking with the kernel.  It works very well and we endorse the
Chantal  product  as software to handle a wide list of new  SCSI  devices
becoming  available such as DAT tape units, etc.  In our case, we use  it
to  connect Exabyte 8200S 8mm tape drives with an Adaptec 1540 controller
to PC ATs hosting SCO XENIX V/386 2.3.2.

Texas  Instruments  has  an Intel 386 based UNIX system,  which  runs  TI
System  V,  which is essentially a PC AT running SCO XENIX  V/386  2.3.2,
without  modification to SCO but supposed OS enhancements and  additions,
along with some serious proprietary hardware changes.

The ROM BIOS is apparently written from the ground up.  Also, they saw it
fit  to  create a proprietary nonstandard primary SCSI controller in  the
interests of speed optimization.  As a result, they had to write a custom
device  driver and add it to SCO's offering to address their  proprietary
controller.   This  also allowed them to boot from a SCSI device  WITHOUT
requiring the "GT" version of SCO XENIX.

We  thought  our  problem would be that the Chantal subsystem  would  get
confused  with the proprietary controller, so we undertook a strategy  to
replace  the proprietary controller all together and make an Adaptec 1540
the  primary controller, so when the Chantal subsystem tried to take over
control,  it would see a device in knows and supports.  Further, to  boot
from  a  SCSI  device now which did not have TI's custom  controller  and
supporting device driver, one requires the GT version of SCO.

It  turns  out that we are unable to get the TI to recognize the  Adaptec
1540  as  the  primary  boot  device down at  the  hardware  level.   All
interrupts  and  addresses along with he DMA channels are  confirmed  set
accurately  along  with  confirmation that the 1540 is  a  fully  working
board.

Senior  technical  staff  at our organization, TI  design  engineers  and
Chantal have all attempted to solve the situation without success.  Thus,
we seek a solution to get the TI model 1300 to recognize the Adaptec 1540
as  the primary controller, or in the alternative, a simple device driver
for the Exabyte 8200S under SCO XENIX V/386, non GT, 2.3.2.

If responses are emailed I will summarize.
-- 
Bill Irwin - TWG The Westrheim Group - Vancouver, BC, Canada
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